Flame-arc lamp and electrode thereof.



G.EGLY. FLAME ARC LAMP AND ELECTRODE THEREFOR,

APPLICATION FILED NOV- 26. l9l5- Patented Apr. 3, i917.

UNITED STATES Parana OFFICE.

GEORG EGLY, 0F BERLIN-TREPTOW, GERMANY, ASSIGNOR TO GEBRUEDER SIEMENS &:

(10., OF BERLIN-TREPTOW, GERMANY,

A GERMAN COYARTNERSHIP.

FLAME-ARQ LAMP AND ELECTRODE THEREFOR.

Specification efiettersPatent.

Application filed November 26, 1815. I Serial No. 63,628,

To all whom it may concern: x Be it known that I Gnoao EGLY. a c1t1- I 1zen ot the (:erman Empire, and residing at llerlin-'Irept(nv, Germany,have invented certain new and useful Improvements in Flame-Arc. Lampsand Electrodes 'lherefor, of which the following is a specification.

This invention relates to flanie-arc lamps and electrodes therefor ofthetype described and claimed in the U. S. Patent No. 1,132,313. In thispatent I have. described a flame-arc lamp in which the formation of slagon the negative electrode prevented by incorporating salts of thealkalis in the negative electrode as an essel'itial constituent evenlydistributed throughout the. entire mass thereof.

According to my present invention I employ boracic acid instead of saltsoi the alltalis.

lt has been found that horacic acid prozeot: the formation of slag stillmore effectively than horates or other salts of alkalis and that thelight of the are is still steadier. The advantage of boracic acid isfound to be particularly greatin open arcdamps, whereas in inclosedarc-lamps the resulting advantage is less marked. It has been found thatthe beneficial action occurs only when the amount of the admixtureexceeds a certain limit depending on the percentage of salt in thepositive. electrode. The correct proportion must he found experimentallyin each case. For example, when positive earbons are used containingabout -30 to 40 per cent. of luminous salts ithas been found that about3 to 5 per cent. of ordinary b6- racic acid are-requir d according tothe nature. of the luminous salts in each case, or a correspondinglysmaller quantity when theanhydrite is employed.

My invention is diagrammatically represented in the accompanying drawingwhere in a denotes the upper or positive. and T1 the lower or negativeelectrode. The former contains an admixture of light-emitting salts,while the latter contains a suitable proportion of boracicacid as anessential ingredient.

Having thus described my invention I claim as new and desire to secureby Letters Patent of the United States:

A flame-arc lamp comprising in combination' a negative electrode.containing as an essential ingredient a slag preventing admixture in theForm of boraeic acid eaenly (llhtl'llillffll throughout the mass of thesaid electrode, and a positive electrode containing luminousadn'nxtures.

(mono EGLY.

ratented'a as, 191m

